Body Color: Black Metallic Expandable Handsets Supported: 6X Multiline Operation Capability: 1-line Operation Conference Call Capability: Up to 4-Way (H/S-H/S-H/S-LINE) Intercom: Handset to Handset/Handset to Base Speakerphone: Yes Volume Control: Talk Volume(Handset): 5-step Speakerphone Volume(Handset) : 7-step Ringer Volume(Handset/Base): 6-step + OFF Ring Tones: 10 (5+5) (Tone+Melody)